[PATCH v10 0/3] leds: trigger: implement a tty trigger
From: Uwe Kleine-König
Date: Fri Dec 18 2020 - 05:44:22 EST
From: Uwe Kleine-König <uwe@xxxxxxxxxxxxxxxxx>
Hello,
here comes v10 of this series. Changes compared to v9 sent with
Message-Id: 20201018204022.910815-1-u.kleine-koenig@xxxxxxxxxxxxxx in
October:
- Bump date and kernel version in ABI doc
- Fix double unlock in error path; found by Pavel
- Don't stop the workqueue in ttyname_store() to
fix error behaviour on memory allocation failure.
Now it continues with the previous configuration instead of
stopping. Also found by Pavel.
Unaddressed review comments by Pavel are:
- Unused assignment to len in ttyname_show
This is wrong
- "Poll every 100 msec... Hmm.... Okay, I guess?"
Yes, I think there is no way around this given the trigger uses
polling. There is no easy way to get notified instead.
- "Are you sure about LED_ON [in the worker]? It should use current
brightness selected by brightness file..."
I found no consistent behaviour in other triggers. ledtrig-gpio
implements a dedicated "desired_brightness" sysfs file, several use
led_cdev->blink_brightness (via led_trigger_blink_oneshot),
ledtrig-cpu uses led_trigger_event with LED_FULL.
- "How is [the data initialized in ledtrig_tty_activate()] protected
from concurrent access from sysfs?"
I think there is no need to protect this. But I'm not sure I
understood the question correctly, so please recheck and if needed
point out the problem you see in more detail.
Uwe Kleine-König (3):
tty: rename tty_kopen() and add new function tty_kopen_shared()
tty: new helper function tty_get_icount()
leds: trigger: implement a tty trigger
.../ABI/testing/sysfs-class-led-trigger-tty | 6 +
drivers/accessibility/speakup/spk_ttyio.c | 2 +-
drivers/leds/trigger/Kconfig | 9 +
drivers/leds/trigger/Makefile | 1 +
drivers/leds/trigger/ledtrig-tty.c | 188 ++++++++++++++++++
drivers/tty/tty_io.c | 85 ++++++--
include/linux/tty.h | 7 +-
7 files changed, 273 insertions(+), 25 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-class-led-trigger-tty
create mode 100644 drivers/leds/trigger/ledtrig-tty.c
--
2.29.2